wxProcess looks like memory leak

code like this:


class ProcessScan(wx.Process):
def __init__(self, parent):
wx.Processinit__(self, parent)

def Terminate(self, pid, status):
thread.processScan.Detach()
thread.processScan.C()
thread.processScan = None


thread.processScan = ProcessScan(self)
thread.processScan.Redirect()

cwd = os.getcwd()
path = self.config_scan.path
os.chdir(path[0:path.rfind('\\')+1])

wx.Execute(self.edit_file_scan.GetValue(), wx.EXEC_ASYNC,
thread.processScan)
os.chdir(cwd)


class read_thread(threading.Thread):

def run(self):
while bThread:
if self.processScan is not None:
stream = ()
if stream is not None and stream.CanRead():
print stream.read(),
del stream
time.sleep(0.01)


When I start the read_thread, the memory used by this program incresed by
4K/3s, even if stream.CanRead() returns False.
Where is the memory leak? Thank you